1. Field of the Invention
The present invention relates to a ceramic electronic component and a method of manufacturing a ceramic electronic component.
2. Description of the Related Art
In recent years, with developments in miniaturization and higher performance of products in fields such as mobile communication devices including mobile phones, AV devices, and computer devices, miniaturization and higher performance of various electronic components used in these devices are also demanded. To address miniaturization and higher performance of such various electronic components, surface mount devices (SMDs) having a conductor (hereinafter, referred to as an “internal conductor”) such as an electrode and wire in the substrate are now mainstream as electronic devices.
An SMD has a printed board on which each component such as an IC chip and other chip components is mounted. As an electronic device mounted on the SMD, a laminated ceramic electronic component obtained by simultaneously calcining a plurality of kinds of ceramic compositions having different material characteristics is used. The laminated ceramic electronic component includes, for example, an LC filter made up of a combination of magnetic material and dielectric material and a circuit substrate (element) containing a capacitor made up of a combination of high dielectric constant material and low dielectric constant material.
With an LC filter, a combination of an inductor portion made of a ceramic material having a low dielectric constant and a high Q factor in order to provide a high self-resonant frequency and a capacitor portion made of a material having excellent temperature characteristics and a high dielectric constant results in an LC element having a high Q factor and excellent temperature characteristics. With a capacitor contained in the circuit substrate, a combination of a high dielectric constant material and a low dielectric constant material results in a reduced distributed capacitance compared with a capacitor made of only a high dielectric constant material and an increased capacity compared with a capacitor made of only a low dielectric constant material.
A known laminated ceramic electronic component is provided as, for example, a circuit substrate created by simultaneously calcining and integrating an insulating layer having a high relative dielectric constant in a microwave band and also a high Q factor and an insulating layer having a low relative dielectric constant (see Japanese Laid-open Patent Publication No. 2001-284807, for example). Another known laminated ceramic electronic component is provided as a dielectric resonator created by arranging and integrally calcining layer materials with different dielectric constants (see Japanese Laid-open Patent Publication No. 61-212101 and Japanese Laid-open Patent Publication No. 02-086188, for example). A still another known laminated ceramic electronic component is provided as a green sheet laminated body in which a glass ceramic layer of third glass ceramic whose composition ratio is intermediate between those of a first green sheet and a second green sheet is placed therebetween (see Japanese Patent No. 2739767, for example).
However, in an electronic device formed by simultaneously calcining different materials to laminate a plurality of dielectric layers, there is a problem that adhesion between dielectric layers may be insufficient, thereby making dielectric layers more likely to peel. Thus, in an electronic device including a ceramic electronic component created by laminating a plurality of dielectric layers, development of ceramic electronic components that are not subject to limitations of materials of dielectric layers to be combined is desired.